Delivery of implantable neurostimulators

ABSTRACT

Apparatus is provided, comprising an implant-storage member ( 24 ), configured to be percutaneously advanced to a tissue ( 10 ) of a subject, and shaped to define (a) a space ( 26 ) that is configured to house an implant ( 22 ) configured to apply a current to at least the tissue, (b) an opening ( 28 ) through which the implant is deliverable to the tissue, and (c) at least one window ( 30 ), configured such that, while the implant is disposed within the space and the implant-storage member is disposed in the tissue, the window facilitates flow of the current therethrough from the implant to the tissue; and a delivery manipulator ( 34 ), reversibly couplable to the implant, and configured to facilitate delivery of the implant through the opening. Other embodiments are also described.

CROSS-REFERENCES TO RELATED APPLICATIONS

The present application is the US National Phase of PCT applicationIB2013/060607, which published as WO 2014/087337, which claims priorityfrom U.S. Provisional Patent Application 61/733,995 to Gross et al.,filed on Dec. 6, 2012, and entitled “Delivery of implantableneurostimulators”, which is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates generally to medical devices, andspecifically to apparatus and methods for use with percutaneousimplants.

BACKGROUND

Neurological disorders affect the nerves, muscles or the brain. Manyneurological disorders reduce or eliminate voluntary recruitment ofmuscles, which may result in loss of ability to perform motor tasks orto maintain systems that depend on muscle activity for their function.Other disorders may cause pain to adjacent tissues.

Neurostimulation is a clinical tool used to treat various neurologicaldisorders. This technique involves modulation of the nervous system byelectrically activating fibers in the body.

SUMMARY OF THE INVENTION

For some applications of the invention, apparatus and techniques aredescribed for percutaneous delivery of an implant. For someapplications, the apparatus and techniques facilitate identifying atarget site and/or delivering the implant to the identified target site.For some applications, the apparatus and techniques facilitateimplanting the implant at a given orientation with respect to the tissuein which the implant is implanted. For some applications, the apparatusand techniques facilitate anchoring the implant to the tissue in whichthe implant is implanted.

For some applications of the invention, a system comprising aninjectable implant, at least one helical electrode, and at least onehelical anchor is described. For some applications, the helical anchorcomprises an antenna configured to wirelessly receive power.

For some applications of the invention, systems are described thatcomprise a nerve cuff having one or more planar antennas, configured towirelessly receive power, and integral with a cuff body that isconfigured to be wrapped around a nerve of a subject. For someapplications, the planar antennas span less than 360 degrees around thenerve. For some applications, a plurality of planar antennas togetherspans at least 360 degrees around the nerve, each of the plurality ofplanar antennas spanning less than 360 degrees (e.g., no more than 180degrees) around the nerve. For some applications, the cuff bodycomprises a helical body, and the configuration of the planar antennasis projected onto the helical body.

There is therefore provided, in accordance with an application of thepresent invention, apparatus for facilitating percutaneous delivery ofan implant to a tissue of a body of a subject, the implant beingconfigured to apply a current to at least the tissue, the apparatusincluding:

an implant-storage member, configured to be percutaneously advanced tothe tissue, and shaped to define:

-   -   a space that is configured to house the implant,    -   an opening through which the implant is deliverable to the        tissue, and    -   at least one window, configured such that, while the implant is        disposed within the space and the implant-storage member is        disposed in the tissue, the window facilitates flow of the        current therethrough from the implant to the tissue; and

a delivery manipulator, reversibly couplable to the implant, andconfigured to facilitate delivery of the implant through the opening.

In an application, the delivery manipulator is configured to facilitatedelivery of the implant by remaining stationary with respect to thetissue while the implant-storage member is withdrawn proximally withrespect to the tissue.

In an application, the implant-storage member includes a hollow needle.

In an application, the implant-storage member:

has a proximal end,

has a distal end that defines the opening, and

has a lateral wall that defines the window between the proximal end andthe distal end.

In an application, the delivery manipulator is slidably coupled to theproximal end of the implant-storage member, and is configured to pushthe implant through the opening.

In an application, the apparatus further includes the implant.

In an application, the apparatus further includes a longitudinal member:

having a distal end configured to be percutaneously advanced into thesubject while coupled to the implant,

having a proximal end configured to be secured to a skin surface of thesubject (1) while the distal end of the longitudinal member is coupledto the implant within the subject, and (2) for a duration of at least 1day, and

being configured to move the implant within the subject by being moved.

In an application:

the implant includes at least two electrodes,

the implant-storage member is shaped to define at least two windows, and

the implant is configured to be disposed within the space such that eachof the electrodes is aligned with a respective window.

There is further provided, in accordance with an application of thepresent invention, apparatus for facilitating percutaneous delivery ofan implant to a target site in a body of a subject, facilitated by atleast one transcutaneous electrode, the apparatus including:

a delivery tool, having a proximal portion and a distal portion, thedistal portion including an implant-storage member, the implant-storagemember configured to be percutaneously advanced toward the target site,and shaped to define (a) a space that is configured to house theimplant, and (b) an opening through which the implant is advanceable;

a guide shaped to define at least one channel and configured tofacilitate percutaneous advancement of the transcutaneous electrode, viathe channel, to the target site; and

a mount, configured:

-   -   to be placed on the skin of the subject in a predetermined        position with respect to the channel, and    -   to be coupled to the delivery tool, the coupling of the mount to        the delivery tool facilitating the delivery of the        implant-storage member to the target site.

In an application, the delivery tool is configured to deliver theimplant to the target site by, when the implant is disposed in thespace, and the implant-storage member is disposed at the target site,withdrawing the implant-storage member proximally with respect to thetarget site while simultaneously holding the implant stationary withrespect to the target site.

In an application, the apparatus further includes the transcutaneouselectrode and an extracorporeal control unit, the extracorporeal controlunit being configured to drive the transcutaneous electrode to apply acurrent to the tissue of the subject, so as to identify the target site.

In an application, the mount includes the guide.

In an application, the guide is configured to be placed on the skin ofthe subject, and the mount is configured to be placed in the givenposition with respect to the channel by being placed in a given positionwith respect to the guide.

In an application:

the guide has a first skin-contacting surface, and is shaped such thatthe channel is generally orthogonal to a plane defined by theskin-contacting surface, and

the mount has a second skin-contacting surface, and is shaped to definea lumen through which the implant-storage member is slidable, the lumenbeing disposed at less than 30 degrees with respect to the secondskin-contacting surface.

In an application, the mount is configured to be coupled to the guide inthe predetermined position with respect to the guide.

In an application, the mount is shaped to define a receptacle withinwhich at least a portion of the guide is placeable.

In an application, the apparatus further includes a depth indicator,configured to indicate a depth of the transcutaneous electrode in thebody of the subject.

In an application, the apparatus further includes the transcutaneouselectrode.

In an application, the depth indicator includes a gauge, configured tobe placed on the skin of the subject in a vicinity of the transcutaneouselectrode.

In an application, the transcutaneous electrode includes markings, thedepth indicator including the markings.

There is further provided, in accordance with an application of thepresent invention, apparatus for facilitating percutaneous delivery ofan implant, the apparatus including:

a rigid delivery tube, having a distal end, a proximal end, and alongitudinal axis therebetween, and shaped to define a lumen configuredto facilitate passage of the implant therethrough; and

at least one flexible longitudinal member having a proximal portion anda distal portion:

-   -   slidably coupled to the rigid delivery tube,    -   configured to pierce tissue of the subject, and    -   having shape memory such that a distal tip of the flexible        longitudinal member has a tendency to be disposed at a first        nonzero angle with respect to the proximal portion,        the apparatus having:

at least one retracted configuration in which the distal tip of theflexible longitudinal member is generally parallel with the longitudinalaxis of the rigid delivery tube, and

an extended configuration in which the distal portion of the flexiblelongitudinal member is disposed distally to the distal end of the rigiddelivery tube, and the distal tip of the flexible longitudinal member isdisposed at a second nonzero angle with respect to the longitudinal axisof the rigid delivery tube.

In an application, the at least one flexible longitudinal memberincludes a flexible wire.

In an application, the at least one flexible longitudinal member isslidable through the lumen of the rigid delivery tube.

In an application, the at least one flexible longitudinal memberincludes nitinol.

In an application, the apparatus further includes a mount, having askin-contacting surface configured to be placed on skin of the subject,the rigid delivery tube and the flexible longitudinal member beingslidably coupled the mount.

In an application, the rigid delivery tube has an angular dispositionwith respect to a plane defined by the skin-contacting surface ofbetween 30 and 45 degrees.

In an application, the apparatus is configured such that, in theextended configuration, an angular disposition of the distal tip of theflexible longitudinal member with respect to the plane is shallower thanthe angular disposition of the rigid delivery tube with respect to theplane.

In an application, the apparatus has a withdrawn retractedconfiguration, and an advanced retracted configuration in which thedistal portion of the flexible longitudinal member and the distal end ofthe rigid delivery tube are disposed further from the mount than in thewithdrawn retracted configuration.

In an application, the apparatus is configured such that, when (1) themount is disposed on the skin of the subject, (2) the apparatus is inthe extended configuration thereof, and (3) the flexible longitudinalmember is disposed in the tissue of the subject, as the apparatus movestoward the advanced retracted configuration thereof, the apparatusdistorts the tissue of the subject.

In an application, the at least one flexible longitudinal memberincludes a flexible tube.

In an application, the at least one flexible longitudinal memberincludes at least a first flexible longitudinal member that includes theflexible tube, and a second flexible longitudinal member, configured topierce the tissue of the subject, and slidable through the flexibletube.

In an application, the second flexible longitudinal member includes aflexible wire.

There is further provided, in accordance with an application of thepresent invention, apparatus for implantation in tissue of a subject,the apparatus including:

an implant body, having a proximal end and a distal end, and alongitudinal axis between the proximal end and the distal end;

at least one electrode;

at least one distal anchor, configured to inhibit movement of theimplant body through the tissue in a distal direction more than in aproximal direction; and

at least one proximal anchor, disposed proximal to the distal anchor,and configured to inhibit movement of the implant body through thetissue in the proximal direction more than in the distal direction.

In an application:

the distal anchor includes at least one barb that protrudes, in thedistal direction, at a nonzero angle with respect to the longitudinalaxis of the implant body, and

the proximal anchor includes at least one barb that protrudes, in theproximal direction, at a nonzero angle with respect to the longitudinalaxis of the implant body.

In an application:

each of the anchors has a constrained state and an unconstrained state,

each of the anchors is configured such that the nonzero angle of thebarb of each anchor is smaller in the constrained state of the anchorthan in the unconstrained state of the anchor.

In an application, the apparatus further includes:

an implant-storage member:

-   -   configured to be percutaneously advanced to the tissue,    -   shaped to define a space that is configured to house the        implant, and an opening through which the implant is        bidirectionally movable,    -   configured to constrain each of the anchors in the respective        constrained state thereof while the respective anchor is        disposed within the space, and    -   configured to move the distal anchor into the constrained state        thereof when the distal anchor is moved through the opening into        the space; and

a delivery manipulator, reversibly couplable to the implant, andconfigured to facilitate bidirectional movement of the implant throughthe opening.

There is further provided, in accordance with an application of thepresent invention, apparatus for use with a nerve of a subject, theapparatus including:

at least one helical electrode, configured to be wrapped around a firstsite on the nerve of the subject;

an injectable implant, configured to be percutaneously implanted in avicinity of the nerve of the subject, and including a control unit thatis configured to drive the at least one helical electrode to apply acurrent to the nerve of the subject;

at least one wire, coupling the injectable implant to the at least onehelical electrode; and

a helical anchor, configured to be wrapped around a second site of thenerve of the subject, and including a brace, the brace being coupled toa portion of the wire that is between the helical electrode and theinjectable implant.

In an application:

the at least one helical electrode includes at least two helicalelectrodes,

the at least one wire includes at least two wires, each wire coupling arespective one of the helical electrodes to the injectable implant, and

the brace is configured to be coupled to a respective portion of each ofthe wires that is between the respective helical electrode and theinjectable implant.

In an application, the helical anchor includes at least one antenna,configured to wirelessly receive energy, and the injectable implant isconfigured to receive the received energy from the antenna.

In an application, the control unit is configured to drive the at leastone electrode in response to the received energy.

There is further provided, in accordance with an application of thepresent invention, apparatus for use with a nerve of a subject, theapparatus including:

a cuff body

-   -   having:        -   first and second mutually-orthogonal lengths on a plane of            the cuff body when the cuff body is unrolled, which define            an area of the cuff body on the plane, and        -   a first face, a second face, and a thickness between the            first face and the second face, and    -   being configured to be wrapped around the nerve such that the        first face faces the nerve, and such that a length of the nerve        covered by the cuff body is defined by the second length of the        cuff body;    -   including at least one electrode, disposed on the first face of        the cuff body; and    -   including at least one planar antenna, coupled to the cuff body        so as to be parallel with the plane of the cuff body, and        configured to wirelessly receive energy; and

circuitry, configured to use the received energy from the planar antennato drive the at least one electrode to apply a current to the nerve.

In an application, the cuff body includes a material, and the planarantenna is disposed within the material of the cuff body.

In an application, the at least one planar antenna includes a pluralityof planar antennas, and a sum of areas spanned by the plurality ofplanar antennas is greater than the area of the cuff body.

In an application, the at least one planar antenna includes n planarantennas, each of the n planar antennas spanning an area that has alength along the first length of the cuff body, that is greater than 1/ntimes the first length of the cuff body.

In an application, the at least one electrode includes two electrodes,the electrodes being disposed at opposite ends of the second length ofthe cuff body from each other.

In an application, each of the electrodes has a longest dimension thatis parallel to the first length of the cuff body.

In an application, the cuff body is configured such that, when the cuffbody is wrapped around the nerve, the cuff body defines a tube, thefirst face defining a 360-degree circumferential wall of the tube.

In an application, the at least one antenna spans an area, and the cuffbody is configured such that, when the cuff body is wrapped around thenerve, a total number of degrees around the circumferential wall thatthe area of the at least one planar antenna spans, is at least 180degrees.

In an application, the at least one antenna spans an area, and the cuffbody is configured such that, when the cuff body is wrapped around thenerve, a total number of degrees around the circumferential wall thatthe area of the at least one planar antenna spans, is at least 360degrees.

In an application, the cuff body is configured such that, when the cuffbody is wrapped around the nerve, the area of the at least one planarantenna circumscribes the circumferential wall.

In an application, the at least one planar antenna includes a pluralityof planar antennas, and the cuff body is configured such that, when thecuff body is wrapped around the nerve, the area of each of the planarantennas spans around less than 360 degrees of the circumferential wall.

In an application, the cuff body is configured such that, when the cuffbody is wrapped around the nerve, the area of each of the planarantennas spans around less than 270 degrees of the circumferential wall.

In an application, the cuff body is configured such that, when the cuffbody is wrapped around the nerve, the area of each of the planarantennas spans around between 90 and 180 degrees of the circumferentialwall.

In an application, the cuff body is configured such that, when the cuffbody is wrapped around the nerve, the area of each of the planarantennas spans around 180 degrees of the circumferential wall.

In an application, the cuff body is configured such that, when the cuffbody is wrapped around the nerve, the area of each of the planarantennas is disposed around 120 degrees of the circumferential wall.

In an application, the plurality of planar antennas includes at least afirst antenna and a second antenna, and the first antenna isrotationally offset around the circumferential wall with respect to thesecond antenna, by between 45 degrees and 180 degrees.

In an application, the plurality of planar antennas includes at least afirst antenna and a second antenna, and the first antenna isrotationally offset around the circumferential wall with respect to thesecond antenna, by between 45 degrees and 60 degrees.

In an application, the plurality of planar antennas includes at least afirst antenna and a second antenna, and the first antenna isrotationally offset around the circumferential wall with respect to thesecond antenna, by between 45 degrees and 90 degrees.

In an application, the plurality of planar antennas includes at least afirst antenna and a second antenna, and the first antenna isrotationally offset around the circumferential wall with respect to thesecond antenna, by between 60 degrees and 120 degrees.

In an application, the plurality of planar antennas includes at least afirst antenna and a second antenna, and the first antenna isrotationally offset around the circumferential wall with respect to thesecond antenna, by between 90 degrees and 120 degrees.

In an application, the at least one planar antenna includes n planarantennas, each of the n planar antennas spanning an area that has alength along the first length of the cuff body, that is generally 1/ntimes as great as the first length of the cuff body.

In an application, the n planar antennas include two planar antennas,each of the two planar antennas spanning an area that has a length alongthe first length of the cuff body that is half as great as the firstlength of the cuff body.

In an application, the area of each of the n planar antennas overlapsthe area of at least another of the n planar antennas.

In an application, the at least one planar antenna includes a pluralityof planar antennas that includes at least a first planar antenna and asecond planar antenna, the first planar antenna spanning a first area,and the second planar antenna spanning a second area.

In an application, the first area and the second area do not overlap.

In an application, the first area and the second area overlap.

In an application, the first area has length along the first length ofthe cuff body, the second area has length along the first length of thecuff body, and the length of the first area overlaps the length of thesecond area.

There is further provided, in accordance with an application of thepresent invention, apparatus for use with a nerve of a subject, thenerve having a longitudinal axis, the apparatus including:

a cuff body, configured to be wrapped at least 360 degrees around thelongitudinal axis; and

a plurality of planar antennas, configured to wirelessly receive power,the plurality of planar antennas being coupled to the cuff body suchthat, when the cuff body is wrapped around the 360 degrees, each of theplanar antennas spans less than 360 degrees around the longitudinalaxis.

In an application, at least one of the planar antennas is disposed ineach rotational position around the longitudinal axis.

In an application, when the cuff body is wrapped around the 360 degrees,at least two of the planar antennas are disposed at a same longitudinalsite.

In an application, when the cuff body is wrapped around the 360 degreesof portion of the nerve, at least a first one of the planar antennas isdisposed at a first longitudinal site of the longitudinal axis, and atleast a second one of the planar antennas is disposed at a secondlongitudinal site of the longitudinal axis that is different to thefirst longitudinal site.

In an application, when the cuff body is wrapped around the 360 degrees,each of the planar antennas spans no more than 270 degrees around thelongitudinal axis.

In an application, when the cuff body is wrapped around the 360 degrees,each of the planar antennas spans between 90 and 180 degrees around thelongitudinal axis.

There is further provided, in accordance with an application of thepresent invention, apparatus for implantation in a vicinity of a tissueof a subject, the apparatus including:

an implant body, configured to be percutaneously delivered to thevicinity of the tissue;

at least one suction chamber, shaped to define at least one window; and

at least one anchor disposed within the suction chamber, the anchor:

-   -   defining a tissue-piercing element,    -   having a first state and a second state, and being        transitionable from the first state to the second state, and    -   being configured such that when the anchor transitions from the        first state toward the second state, the tissue-piercing element        moves with respect to the window.

In an application, the first state includes a constrained state, theapparatus including a constraining member, configured to constrain theanchor in the constrained state, and the anchor is configured toautomatically transition toward the unconstrained state when theconstraining member stops constraining the anchor.

In an application, the apparatus is configured to draw a portion of thetissue through the window into the suction chamber when an at leastpartial vacuum is drawn into the suction chamber, and thetissue-piercing element is configured to penetrate the portion of thetissue when the anchor transitions from the first state toward thesecond state.

There is further provided, in accordance with an application of thepresent invention, a method for use with a subject, the methodincluding:

inserting, through skin of the subject and into tissue of the subject,an implant-storage member and an implant, the implant-storage memberbeing shaped to define a space configured to house the implant, a distalopening, and at least one window;

while the implant is disposed within the space, driving a current, usingthe implant, into tissue of the subject through the at least one window;

removing the implant from the space via the distal opening by proximallywithdrawing the implant-storage member.

In an application, proximally withdrawing the implant-storage memberincludes leaving a longitudinal member coupled to the implant such thata distal portion of the longitudinal member is disposed in the tissue,and the method further includes securing a proximal portion of thelongitudinal member to a skin surface of the subject.

In an application, inserting includes inserting such that the implant isdisposed at a first site of the tissue, driving the current includesdriving a first application of the current and the method furtherincludes:

after a start of the driving of the first application of the current,measuring a parameter of the subject; and

subsequently to the measuring and prior to the removing, moving theimplant to a second site of the tissue, and subsequently driving asecond application of the current.

In an application, driving the current includes wirelessly powering theimplant to drive the current.

In an application, removing the implant includes removing the implant byproximally withdrawing the implant-storage member while providing areference force to the implant using a delivery manipulator, reversiblycoupled to the implant.

In an application, the implant-storage member has a lateral wall thatdefines the at least one window, and driving the current includesdriving the current through the at least one window in the lateral wall.

In an application, the implant includes at least two electrodes, thelateral wall defines at least two windows, and driving the currentincludes driving the current via the at least two electrodes while eachelectrode is aligned with a respective window.

There is further provided, in accordance with an application of thepresent invention, a method, including:

placing, on skin of a subject, a guide shaped to define at least onechannel;

advancing at least one transcutaneous electrode through the at least onechannel and percutaneously toward a target site in tissue of thesubject;

driving the at least one electrode to apply an electrical current to thetissue of the subject, and detecting a parameter of the subject thatvaries in response to the applying of the electrical current;

at least in part responsively to the detected parameter, measuring adepth of the transcutaneous electrode in the tissue using a depthindicator;

at least in part responsively to the measured depth, placing a mount onthe skin of the subject and in a predetermined position with respect tothe channel; and

while the mount is in the predetermined position with respect to thechannel, delivering to the target site, using a delivery tool coupled tothe mount, an implant disposed within a space defined by animplant-storage member at a distal end of the delivery tool, thedelivery being facilitated by the coupling of the delivery tool to themount.

In an application, the method further includes, subsequently todelivering, moving the implant out of the space via an opening definedby the implant-storage member by withdrawing the implant-storage memberproximally while holding the implant stationary with respect to thetarget site.

In an application, placing the mount includes placing the mountsubsequently to driving the at least one electrode to apply theelectrical current.

In an application, the method further includes, subsequently to placingthe mount, coupling the delivery tool to the mount and advancing theimplant-storage member through a lumen defined by the mount.

In an application, the mount includes the guide, and placing the mountincludes placing the mount at the same time as placing the guide.

In an application:

advancing the at least one electrode percutaneously includes advancingthe at least one electrode percutaneously at an angle that is generallyorthogonal to a plane defined by a first skin-contacting surface of theguide, and

delivering the implant includes advancing the implant-storage memberpercutaneously at an angle that is less than 30 degrees with respect toa second skin-contacting surface defined by the mount.

In an application, placing the mount in the predetermined positionincludes coupling the mount to the guide in the predetermined position.

In an application, placing the mount in the predetermined positionincludes placing a receptacle defined by the mount around at least aportion of the guide.

In an application, the depth indicator includes a gauge, and measuringthe depth includes placing the gauge on the skin of the subject in avicinity of the transcutaneous element.

In an application, the method further includes, subsequently tomeasuring the depth, and prior to placing the mount, selecting the mountfrom a plurality of mounts at least in part responsively to the measureddepth.

In an application, the method further includes, subsequently tomeasuring the depth, adjusting the mount at least in part responsivelyto the measured depth.

There is further provided, in accordance with an application of thepresent invention, a method, including:

percutaneously advancing at least one flexible longitudinal memberthrough tissue of a subject such that shape memory of the flexiblelongitudinal member disposes a distal tip of the flexible longitudinalmember at a nonzero angle with respect to a proximal portion of theflexible longitudinal member;

subsequently, distally advancing a rigid delivery tube along theflexible longitudinal member and into the tissue, such that theapparatus moves into a retracted configuration in which the distal tipof the flexible longitudinal member is generally parallel with alongitudinal axis of the rigid delivery tube; and

subsequently, delivering an implant to the tissue via the rigid deliverytube.

In an application, percutaneously advancing the at least one flexiblelongitudinal member includes piercing the tissue with the at least oneflexible longitudinal member.

In an application, advancing the at least one flexible longitudinalmember includes advancing a flexible wire.

In an application, advancing the at least one flexible longitudinalmember includes advancing the at least one flexible longitudinal memberthrough the rigid delivery tube, and advancing the rigid delivery tubeincludes sliding the rigid delivery tube over the at least one flexiblelongitudinal member.

In an application, advancing the at least one flexible longitudinalmember includes advancing at least one flexible longitudinal member thatincludes nitinol.

In an application, the method further includes placing a skin-contactingsurface of a mount on skin of the subject, and advancing the at leastone flexible longitudinal member includes sliding the at least oneflexible longitudinal member with respect to the mount, and advancingthe rigid delivery tube includes sliding the rigid delivery tube withrespect to the mount.

In an application, sliding the rigid delivery tube with respect to themount includes sliding the rigid delivery tube at an angulardisposition, with respect to a plane defined by the skin-contactingsurface, of between 30 and 45 degrees.

In an application, advancing the rigid delivery tube along the flexiblelongitudinal member includes increasing an angular disposition of thedistal tip of the flexible longitudinal member with respect to theplane.

In an application, advancing the rigid delivery tube along the flexiblelongitudinal member includes deforming the tissue of the subject.

In an application, delivering the implant includes delivering theimplant while the tissue is deformed, and the method further includes,subsequently to delivering the implant, withdrawing the rigid deliverytube from the tissue.

In an application, advancing the at least one flexible longitudinalmember includes advancing a flexible tube.

In an application, advancing the flexible tube includes advancing afirst flexible longitudinal member, and further includes advancing asecond flexible longitudinal member through the flexible tube and intothe tissue.

In an application, advancing the second flexible longitudinal memberincludes advancing a flexible wire.

There is further provided, in accordance with an application of thepresent invention, a method, including:

percutaneously delivering an implant into a subject;

drawing tissue of the subject via a window of the implant into a suctionchamber of the implant; and

driving an anchor having a tissue-piercing element through the tissuewithin the suction chamber, the tissue-piercing element remaining withinsuction chamber.

There is further provided, in accordance with an application of thepresent invention, apparatus for use with a subject, including:

an implant, configured to be percutaneously injected into tissue of thesubject; and

a longitudinal member, reversibly couplable to the implant, and:

the apparatus is configured to be left, for at least 1 day, in a statein which:

-   -   the implant is disposed within the tissue,    -   a distal portion of the longitudinal member is coupled to the        implant,    -   a proximal portion of the longitudinal member is secured to a        skin surface of the subject, and    -   the implant is movable within the subject by moving the proximal        portion of the longitudinal member.

The present invention will be more fully understood from the followingdetailed description of applications thereof, taken together with thedrawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-D are schematic illustrations of a system for facilitatingdelivery of an implant in a tissue of a subject, in accordance with someapplications of the invention;

FIGS. 2A-G are schematic illustrations of a system comprising animplant, which comprises an implant body, at least one electrode, andone or more directionally-biased anchors, in accordance with someapplications of the invention;

FIG. 3 is an schematic illustration of an implant comprising an implantbody, at least one electrode, and one or more directionally-biasedanchors, in accordance with some applications of the invention;

FIGS. 4A-H are schematic illustrations of a system for facilitatingpercutaneous delivery of an implant to a target site in the body of asubject, in accordance with some applications of the invention;

FIGS. 5A-M are schematic illustrations of a system for facilitatingpercutaneous delivery of an implant, the system comprising a rigiddelivery tube and at least a first flexible longitudinal member,slidably coupled to the delivery tube, in accordance with someapplications of the invention;

FIGS. 6A-C are schematic illustrations of an implant configured to bepercutaneously implanted in a tissue of a subject, in accordance withsome applications of the invention;

FIGS. 7A-B are schematic illustrations of a system for use with a nerveof a subject, in accordance with some applications of the invention;

FIGS. 8A-C are schematic illustrations of a system for use with a nerveof a subject, in accordance with some applications of the invention;

FIGS. 9A-C are schematic illustrations of a system for use with nerve,in accordance with some applications of the invention;

FIGS. 10-14 are schematic illustrations of planar antennaconfigurations, in accordance with respective applications of theinvention;

FIG. 15 is a schematic illustration of a helical element comprising ahelical body and a plurality of planar antennas, in accordance with someapplications of the invention; and

FIGS. 16-18 are schematic illustrations of systems comprising animplant, and at least one longitudinal member having a distal portionconfigured to be implanted with the implant, and a proximal portionconfigured to remain outside of the subject, in accordance with someapplications of the invention.

DETAILED DESCRIPTION OF EMBODIMENTS

Reference is made to FIGS. 1A-D, which are schematic illustrations of asystem 20 for facilitating delivery of an implant 22 in a tissue 10 of asubject, in accordance with some applications of the invention. System20 comprises an implant-storage member 24, which typically comprises atubular member. FIG. 1A shows member 24 alone, and FIGS. 1B-D showmember 24 being used in combination with other components of system 20,to delivery implant 20 to tissue 10.

Implant-storage member 24 is shaped to define a space 26, configured tohouse implant 22. For some applications in which member 24 comprises atubular member, space 26 comprises at least part of a lumen that extendsthe length of the tubular member, from a proximal end to a distal endthereof. For some applications, member 24 comprises a hollow needle.Implant-storage member 24 is shaped to further define an opening 28,configured to facilitate passage of implant 22 therethrough, and atleast one window 30. Typically, member 24 comprises a lateral wall 29,that extends from the proximal end to the distal end of member 24, andthat is shaped to define window 30.

Typically, implant 22 comprises at least one electrode 32, and isconfigured to apply a current (e.g., a treatment current) to the subject(e.g., to tissue 10, or to a different target tissue, or anatomical siteor structure, such as to a nerve of the subject). Further typically,implant 22 comprises two or more electrodes 32, and implant-storagemember 24 is shaped to define two or more respective windows 30,positioned such that, when implant 22 is housed within space 26, eachelectrode is aligned with a respective window. Member 24 (e.g., windows30 thereof) is configured to facilitate application of the current byimplant 22 (e.g., to the tissue), while implant 22 is disposed in space26. Member 24 thereby facilitates the positioning of implant 22 at apreferred location within tissue 10 (e.g., in a vicinity of a targettissue, such as in a location in which the current has maximal effect ona physiological parameter of the subject), prior to deployment of theimplant through opening 28. That is, a response to the current driven byimplant 22 may be detected, and according to that response, the implantis deployed.

FIG. 1B shows implant-storage member 24, housing implant 22, having beenpercutaneously delivered to a first site within tissue 10. Electrodes 32of implant 22 are aligned with windows 30. Electrodes 32 drive thecurrent (e.g., into tissue 10), and the physiological parameter ismeasured (e.g., after a start of the application of the current, such asduring the application of the current or after the application of thecurrent). If the response to the current is acceptable (e.g., greaterthan a threshold response), the implant may be deployed. Alternatively,as shown in FIG. 1C, member 24 may be repositioned within tissue 10(e.g., to a second site within the tissue, such as a deeper site), untilan acceptable response is achieved, at which point implant 22 isdeployed. As shown in FIG. 1D, implant 22 is typically deployed byholding implant 22 still with respect to tissue 10 (e.g., using adelivery manipulator 34 that is reversibly couplable to the implant),while withdrawing implant-storage member 24 proximally, such that theimplant is delivered through opening 28.

Typically, implant 22 is wirelessly powered, and is configured to applythe current in response to receiving the wireless power. For someapplications, the driving of the current described with reference toFIGS. 1B and 1C is driven in this wireless manner. For some application,the driving of the current described with reference to FIGS. 1B and 1Cis driven by a control unit via a wire disposed within manipulator 34.For example, it may be desirable to identify a suitable position forimplant 22 within tissue 10 independently of any variables caused by theuse of wireless power, and only subsequently test and/or calibrate thetransmission and/or reception of the wireless power.

Reference is made to FIGS. 2A-G, which are schematic illustrations of asystem 50, comprising an implant 52, which comprises an implant body 53,at least one electrode 56 (e.g., two electrodes 56) and one or moredirectionally-biased anchors 54, in accordance with some applications ofthe invention. Implant 52 comprises one or more proximal anchors 54 a ata distal portion of the implant, and typically further comprises one ormore distal anchors 54 b at a proximal portion of the implant, typicallydisposed in the opposite orientation to anchors 54 a. Distal anchors 54a are configured to inhibit movement of the implant (e.g., of implantbody 53) through tissue 10, in a distal direction more than in aproximal direction. Similarly, proximal anchors 54 b are configured toinhibit movement of the implant in a through the tissue, in the proximaldirection more than in the distal direction.

Typically, distal anchors 54 b comprise at least one barb thatprotrudes, in the distal direction, at a nonzero angle alpha_1 withrespect to a longitudinal axis 58 of the implant body (e.g., isdeflected with respect to the longitudinal axis; shown in FIG. 2G).Similarly, proximal anchors 54 a comprise at least one barb thatprotrudes, in the proximal direction, at a nonzero angle with respect tolongitudinal axis 58. For some applications, and as shown with referenceto FIGS. 2A-G, the barbs of anchors 54 b protrude radially from thelateral surface of implant body 53. Typically, anchors 54 (e.g., anchors54 a and 54 b) have a constrained state and an unconstrained state,angle alpha_1 being greater in the unconstrained state than in theconstrained state. For some applications, and as shown with reference toFIGS. 2A-G, in the constrained state, the anchors are held against thelateral surface of implant body 53, and move away from the lateralsurface when moving into the unconstrained state. Typically, system 50further comprises an implant-storage member 60, shaped to define a spacethat is configured to house implant 52, and an opening 62 though whichthe implant is bidirectionally movable. System 50 also typically furthercomprises a delivery manipulator 64, configured to facilitate thebidirectional movement of implant 52 through opening 62.

FIG. 2A shows implant 52 having been delivered, within implant-storagemember 60, to a first site within tissue 10. Implant-storage member 60is then withdrawn proximally with respect to tissue 10 while implant 52is held still with respect to the tissue, thereby exposing at leastelectrodes 56 of implant 52, from opening 62 (FIG. 2B). Implant 52(e.g., electrodes 56 thereof) is driven to apply a current (e.g., atreatment current) to the tissue, and a response of a physiologicalparameter of the subject to the current is detected, e.g., as describedhereinabove with respect to system 20, mutatis mutandis. If the responseto the current is acceptable (e.g., greater than a threshold response),the implant may be deployed. Alternatively, as shown in FIG. 2C, member60 may be advanced back over implant 52, and repositioned within tissue10 (e.g., to a second site within the tissue, such as a deeper site),until an acceptable response is achieved. FIG. 2D shows member 60 andimplant 52 at a second site within the tissue, and FIG. 2E shows implant52, re-exposed from opening 62, in order to re-apply the current so asto test the second location.

It is to be noted that, for the “test” exposures shown in FIGS. 2B and2E, distal anchors 54 a, but not proximal anchors 54 b, are exposed fromopening 62. The angular disposition of anchors 54 a with respect toimplant body 53 facilitates the advancing of member 60 over implant 52,for repositioning within tissue 10. Furthermore, this angulardisposition also facilitates proximal movement of implant 52 while theimplant is in this state (e.g., with distal anchors 54 a and electrodes56 exposed). FIG. 2F shows such movement, which may be used for finaladjustment (e.g., “fine tuning”) of the position of the implant. Forsome applications, during such proximal movement, anchors 54 a move atleast slightly toward longitudinal axis 58.

Once a desired site has been established, implant 52 is deployed bywithdrawing member 60 such that all of the implant, including proximalanchors 54 b, are exposed from opening 62 (FIG. 2G). As describedhereinabove, proximal anchors 54 b inhibit proximal movement of theimplant. This inhibition, in combination with that provided by anchors54 a, which inhibit distal movement of the implant, anchors the implantwithin tissue 10.

Reference is made to FIG. 3, which is an schematic illustration of animplant 70, comprising an implant body 73, at least one electrode 76,and one or more directionally-biased anchors 74, in accordance with someapplications of the invention. Anchors 74 typically comprise one or moreproximal anchors 74 a and one or more distal anchors 74 b. Distalanchors 74 a are configured to inhibit movement of the implant (e.g., ofimplant body 53) through tissue 10, in a distal direction more than in aproximal direction. Similarly, proximal anchors 74 b are configured toinhibit movement of the implant in a through the tissue, in the proximaldirection more than in the distal direction.

Typically, distal anchors 74 b comprise (1) a rod 80 b that protrudesdistally from implant body 73 on a longitudinal axis 78 of the implant,and (2) at least one barb 82 b that protrudes, in the distal direction,at a nonzero angle alpha_2 with respect to the longitudinal axis (e.g.,is deflected with respect to the longitudinal axis). Similarly, proximalanchors 74 a comprise (1) a rod 80 a that protrudes distally fromimplant body 73 on longitudinal axis 78 of the implant, and (2) at leastone barb 82 a that protrudes, in the proximal direction, at a nonzeroangle with respect to the longitudinal axis.

For some applications, implant 70 is used in combination with apparatusand techniques described with reference to FIGS. 2A-G, mutatis mutandis.

Reference is again made to FIGS. 2A-G and 3. For some applications ofthe invention, the directionally-biased anchors, and/or the barbsthereof, crudely represent ears of wheat or barley.

Reference is made to FIGS. 4A-H, which are schematic illustrations of asystem 90, for facilitating percutaneous delivery of an implant 92 to atarget site in the body of a subject, in accordance with someapplications of the invention. For some applications, implant 92comprises an implant described elsewhere herein, such as implant 20,implant 50, and/or implant 70. FIG. 4A shows the components of system90. System 90 comprises a delivery tool 94, having a proximal portion 96and a distal portion 98, the distal portion comprising animplant-storage member 100, configured to be percutaneously advancedtoward the target site, and shaped to define a space that is configuredto house the implant, and an opening through which the implant isadvanceable. For some applications, implant-storage member 100 comprisesan implant-storage member described elsewhere herein, such asimplant-storage member 24 and/or implant-storage member 60. Typically,proximal portion 96 comprises a handle 97.

System 90 further comprises a guide 104, shaped to define one or morechannels 102 that are configured to facilitate advancement of one ormore respective transcutaneous electrodes, via a respective channel,through the skin of the subject, and to the target site. It is to benoted that throughout the present application, including thespecification and the claims, the term “transcutaneous electrode” refersto an electrode that is configured to be placed through the skin of thesubject while being coupled to extracorporeal apparatus, e.g., as shownin FIG. 4B, and that is typically placed temporarily. The term“transcutaneous electrode” is used so as to distinguish such anelectrode from other electrodes described in the present application,such as an electrode that is a component of a percutaneously-implantedimplant.

System 90 further comprises a mount 110, configured to be placed on theskin of the subject in a predetermined position with respect to channels102, and to be coupled to the delivery tool so as to facilitate deliveryof the implant-storage member (and thereby the implant) to the targetsite (e.g., the site to which the transcutaneous electrodes are advancedvia channels 102). Typically, mount 110 is configured to be placed in apredetermined position with respect to guide 104 (e.g., to be coupled toguide 104 in the predetermined position). For example, and as shown inFIGS. 4A-H, mount 110 may be shaped to define a receptacle 112 withinwhich at least a portion of guide 104 is placeable. For someapplications, mount 110 comprises and/or is integral with guide 104,and/or itself defines channels 102.

Mount 110 is further configured to be coupled to delivery tool 94, suchthat the delivery tool (e.g., implant-storage member 100 thereof) isplaced in a given position with respect to channels 102. For example,mount 110 may be shaped to define a cradle 114, configured to receivehandle 97 of delivery tool 94, and/or a lumen 116, configured to receivedistal portion 98 of the delivery tool. Cradle 114 and lumen 116 aredisposed at a given angular disposition alpha_4 with respect to askin-facing side (e.g., a skin-contacting surface 118) of mount 110.Typically, angle alpha_4 is less than 30 degrees and/or greater than 10degrees (e.g., between 10 and 30 degrees).

System 90 typically further comprises a depth indicator 120, such as agauge 122 (e.g., a plurality of graduated markings), configured toindicate a depth of insertion of the transcutaneous electrodes, asdescribed in more detail hereinbelow.

FIGS. 4B-H show system 90 being used to facilitate implantation ofimplant 92, in accordance with some applications of the invention. It isto be noted that system 90 is shown being used to facilitateimplantation of implant 92 in a leg 12 of the subject in a vicinity of atibial nerve 14 of the subject, by way of illustration, and not by wayof limitation. Guide 104 is placed on the skin of the subject, andtranscutaneous electrodes 130 are advanced, through channels 102 ofguide 104, through the skin of the subject, and into a tissue of thesubject (FIG. 4B). Electrodes 130 are driven (e.g., by an extracorporealcontrol unit 132) to apply (e.g., to the tissue of the subject) acurrent that is similar (e.g., identical) to a current that implant 92is configured to apply. Guide 104 and electrodes 130 may be repositionedmultiple times until a target site is identified, such as a site atwhich the current has a maximal effect on a detected physiologicalparameter of the subject.

In addition to repositioning of guide 104 at different sites on the skinof the subject, electrodes 130 may be repositioned at different depthswithin the tissue of the subject. For some applications, the depth ofthe target site (e.g., the depth at which the electrodes provide maximaleffect) is be determined using depth indicator 120. For example, gauge122 may be placed next to electrodes 130, and the depth determined byobserving the position of a part of the electrodes (e.g., a proximal endof the electrodes) with respect to graduated markings on the gauge (FIG.4C). Alternatively or additionally, electrodes 130 may comprise gradatedmarkings to indicate a depth of the electrodes within the tissue.

Subsequently, mount 110 is placed on the skin of the subject, in thegiven position with respect to guide 104, e.g., by placing at least aportion of guide 104 within receptacle 112 (FIG. 4D). For someapplications, system 90 comprises a plurality of mounts 110, each mountbeing configured to hold delivery tool 94 at a different angulardisposition with respect to the skin of the subject, such as by eachrespective cradle 114 and/or lumen 116 having a different angulardisposition with respect to skin-contacting surface 118 of the mount.Alternatively, mount 110 (e.g., cradle 114 and/or lumen 116 thereof) maybe adjustable. An operating physician selects one of the plurality ofmounts, or adjusts the adjustable mount, according to the determineddepth of the target site. For some applications, gauge 122 iscolor-coded, and each of the plurality of mounts 110 is coloredrespectively, to facilitate correct selection by the operatingphysician.

Subsequently, mount 110 is secured to the skin (e.g., using adhesivetape 128), and delivery tool 94 is coupled to the mount, such as by (1)sliding the distal portion of the delivery tool, comprisingimplant-storage member 100, through the lumen of the mount and into thetissue of the subject, and (2) coupling handle 97 of the delivery toolto the cradle of the mount (FIG. 4E). The positioning of mount 110 withrespect to guide 104, and the coupling of the delivery tool to the mount(and, optionally, the selection and/or adjustment of the mount inresponse to determining the depth of transcutaneous electrodes 130),facilitate the positioning of member 100, housing implant 92, at thetarget site that was previously determined using the transcutaneouselectrodes.

Implant 92 is subsequently deployed by withdrawing implant-storagemember 100 proximally while the implant is held still with respect tothe tissue, thereby leaving the implant exposed at the target site (FIG.4F). For some applications, tool 94 comprises a delivery manipulator 134(typically similar to delivery manipulators 34 and/or 64 describedhereinabove with respect to FIGS. 1A-D and 2A-G, respectively), whichholds implant 92 in place in this manner. For such applications, thedelivery manipulator is subsequently decoupled from implant 92 (FIG.4G). System 90 is subsequently removed from the subject, leaving implant92 at the target site (FIG. 4H).

Reference is made to FIGS. 5A-M, which are schematic illustrations of asystem 150 for facilitating percutaneous delivery of an implant 170, thesystem comprising a rigid delivery tube 152 and at least a firstflexible longitudinal member, slidably coupled to the delivery tube, inaccordance with some applications of the invention. The first flexiblelongitudinal member is configured such that a distal portion thereof hasa tendency to be disposed at a nonzero angle with respect to a proximalportion thereof, such that a distal tip of the first flexiblelongitudinal member (e.g., a distal tip of the distal portion thereof)is disposed at a nonzero angle with respect to the proximal portion ofthe first flexible longitudinal member. That is, the first flexiblelongitudinal member is configured such that the distal portion and/ordistal tip thereof have a tendency to be deflected with respect to theproximal portion thereof. For example, the first flexible longitudinalmember may have shape memory, e.g., may comprise a shape memory materialsuch as nitinol. Typically, the first flexible longitudinal membercomprises a flexible tube 154, having a distal portion 158 and a distaltip 159, and system 150 further comprises a second flexible longitudinalmember, typically comprising a wire 156, slidable through tube 154. Forsome applications, wire 156 also comprises a shape memory material suchas nitinol. Typically, tube 154 and/or wire 156 are configured to piercetissue of the subject. For example, tube 154 and/or wire 156 may eachhave a sharp distal tip and/or may be sufficiently rigid that a pushingforce applied to the proximal end can drive the tube and/or wire throughthe tissue.

For some applications, (1) implant 170 comprises and/or is similar toanother implant described herein, such as implant 22, implant 52,implant 70, implant 92, implant 180 or implant 206, mutatis mutandis,and/or (2) system 150 may be used to facilitate implantation of theseother implants. Typically, system 150 comprises a mount 160, configuredto be placed on the skin of the subject, rigid delivery tube 152,flexible tube 154 and wire 156 being slidably coupled to the mount.Typically, flexible tube 154 is disposed and slidable within deliverytube 152, and wire 156 is disposed and slidable within flexible tube154.

System 150 has at least one retracted configuration in which distalportion 158 of tube 154 is disposed within (e.g., retracted into) tube152, and is thereby held straight by tube 152, such that the distalportion and/or distal tip 159 is generally parallel with thelongitudinal axis of tube 152 (e.g., to be coaxial with tube 152). FIGS.5A-B show system 150 in a first, withdrawn retracted configuration(described in more detail hereinbelow), and FIG. 5J shows system 150 ina second, advanced retracted configuration (described in more detailhereinbelow), in which the tube 152 and tube 154 are disposed furtherfrom mount 160 than when the system is in the withdrawn retractedconfiguration. System 150 has an extended configuration (FIGS. 5C-D,described in more detail hereinbelow) in which distal portion 158 oftube 154 is disposed outside of tube 152 (e.g., distal to the distal endof tube 152), and due to the shape memory, is disposed at a nonzeroangle with respect to longitudinal axis 153 of tube 152, such thatdistal tip 159 of tube 154 is disposed at a nonzero angle alpha_3 withrespect to longitudinal axis 153 (FIG. 5C).

It is to be noted that system 150 is shown being used to facilitateimplantation of implant 170 in leg 12 of the subject in a vicinity oftibial nerve 14 of the subject, by way of illustration, and not by wayof limitation. For example, system 150 may be used at other sites of thesubject, such as to implant the implant in a vicinity of another tissue,such as another nerve of the subject.

Mount 160 is placed on leg 12 of the subject such that a skin-facingside (e.g., a skin-contacting surface 161) of the mount is in contactwith the skin of the subject, typically while system 150 is in thewithdrawn retracted configuration (FIGS. 5A-B). Tube 152 is disposed atan angle alpha_5 with respect to a plane defined by skin-contactingsurface 161. Angle alpha_5 is typically greater than 30 degrees and/orless than 45 degrees (e.g., between 30 and 45 degrees).

FIGS. 5A-B show tube 152 (e.g., a distal end thereof) protruding out ofmount 160 (e.g., past skin-contacting surface 161 thereof) andpenetrating the skin of leg 12. Typically, mount 160 is placed (e.g.,secured) on the skin while tube 152 does not protrude in this manner,and tube 152 is subsequently advanced through the skin. For example,tube 152 (e.g., a distal end thereof) may be disposed within mount 160while the mount is placed on the skin, or may be introduced into themount subsequently to the placement of the mount on the skin.Alternatively, mount 160 is placed (e.g., secured) on the skin whiletube 152 protrudes past skin-contacting surface 161. For someapplications, tube 152 (e.g., the distal end thereof) does not protrudefrom mount 160 (e.g., does not penetrate the skin) until the stepdescribed with reference to FIG. 5G.

For some applications, system 150 is used in combination with apparatusand/or methods described hereinabove with reference to FIGS. 4A-H, so asto facilitate delivery of implant 170 to a target site. For example,guide 104, described hereinabove as a component of system 90, may bepreviously placed on the skin to provide channels for transcutaneouselectrodes for identifying the target site, and as shown with referenceto FIGS. 5A-M, subsequently used to facilitate placement of mount 160,as described hereinabove with reference to FIGS. 4A-H, mutatis mutandis.Similarly, mount 160 may be secured to the skin using adhesive tape 128(not shown in FIGS. 5A-M).

Subsequently, flexible tube 154 is extended out of tube 152, therebymoving system 150 into the extended configuration thereof (FIGS. 5C-D).As described hereinabove, due to shape memory, a distal portion 158 oftube 154 responsively bends such that distal tip 159 of tube 154 isdisposed at nonzero angle alpha_3 with respect to longitudinal axis 153of tube 152.

Typically, the angle at which distal portion 158 (e.g., distal tip 159)of tube 154 is disposed with respect to the plane of the skin of thesubject, and with respect to tibial nerve 14, is shallower than that atwhich tube 152 is disposed with respect to the plane of the skin of thesubject, and with respect to tibial nerve 14. For example, alongitudinal axis 155 of distal portion 158 (e.g., of distal tip 159)may be disposed at less than 20 degrees, such as less than 10 degrees,e.g., less than 5 degrees, to the skin and/or to the tibial nerve. Forsome applications, and as shown in FIG. 5E, axis 155 is generallyparallel with tibial nerve 14. Typically, and as shown in FIG. 5E,system 150 (e.g., tube 154) is configured such that, in the extendedconfiguration, portion 158 is disposed, with respect to the planedefined by skin-contacting surface 161, at a shallower angle than istube 152 (e.g., portion 158 is substantially parallel to the planedefined by surface 161).

For applications in which system 150 comprises wire 156, wire 156 issubsequently advanced through tube 154, and further into the tissue(FIGS. 5E-F). For some applications, wire 156 moves further along axis155. For some applications, wire 156 has shape memory, and a distal endof the wire is disposed at a nonzero angle with respect to axis 155.

Rigid delivery tube 152 is advanced distally, thereby moving system 150into the advanced retracted configuration (FIGS. 5G-J). FIGS. 5G-I showtube 152 having been advanced over tube 154, and FIG. 5J shows tube 152having been advanced further, over wire 156. For some applications,system 150 only comprises one flexible longitudinal member, and tube 152is advanced over the one flexible longitudinal member. As tube 152 isadvanced, tube 154 and wire 156 are straightened, and the tissue in thevicinity of the tube and wire is distorted responsively. As shown inFIGS. 5G-J, this distortion may include distortion (e.g., bending,pressing, and lifting), of skin, subcutaneous tissue, and tibial nerve14. For some applications, this bending maintains the shallow anglebetween nerve 14, and wire 156 (and distal end 158 of tube 152) as wire156 (and distal end 158) are brought into alignment with longitudinalaxis 153 of tube 152. That is, the bending of nerve 14 brings alongitudinal axis 163 of a portion of nerve 14 into closer alignmentwith axis 153 (e.g., parallel to axis 153). For some applications, theflexible longitudinal member (e.g., tube 154 and/or wire 156) therebyacts as an anchor that draws progressive portions of tissue toward axis163 as tube 152 is advanced over progressive portions of the flexiblelongitudinal member.

For some applications in which guide 104 is used to facilitate placementof mount 160, the guide is removed from the skin once the mount has beenplaced on (e.g., and secured to) the skin of the subject. FIG. 5G showsguide 104 having been removed after the step illustrated in FIG. 5F andthe step illustrated in FIG. 5H. However, it is to be understood thatguide 104 may be removed at another stage in the procedure, or may beleft in place until the end of the procedure.

Subsequently, tube 154 and wire 156 are removed from the tissue (e.g.,by removing the tube and wire from mount 160), leaving the distal end ofrigid delivery tube 152 disposed in the tissue (FIG. 5K). Implant 170 issubsequently delivered, via tube 152, to the tissue (FIG. 5L). Forexample, an delivery manipulator 168, reversibly coupled to implant 170,may be advanced through delivery tube 152. For some applications,delivery manipulator 168 comprises and/or is similar to another deliverymanipulator described herein, such as delivery manipulators 34, 64, and134. Due to the angle at which tube 152 is disposed, implant 170 isthereby delivered at a shallow angle with respect to nerve 14 (e.g.,generally parallel with nerve 14). For some applications, implant 170comprises a plurality of electrodes (e.g., as described hereinabove forimplant 22, mutatis mutandis) and positioning of the implant at thisshallow angle with respect to nerve 14 results in positioning of each ofthe electrodes at a similar distance (e.g., the same distance) from thenerve. Delivery tube 152 and the remainder of system 150 are thenremoved from the body of the subject. Removal of delivery tube 152allows the tissue to return to its original state (e.g., allows nerve 14to straighten), implant 170 remaining in its angular disposition withrespect to the tissue (e.g., with a longitudinal axis of the implantgenerally parallel with nerve 14), as shown in FIG. 5M.

Reference is made to FIGS. 6A-C, which are schematic illustrations of animplant 180 configured to be percutaneously implanted in a tissue 182 ofa subject, in accordance with some applications of the invention.Implant 180 comprises an implant body 184, typically comprising acontrol unit and/or circuitry, one or more (e.g., two) suction chambers186, and one or more (e.g., two) anchors 188, disposed within arespective suction chamber. Each suction chamber is shaped to define awindow 194, and each anchor has a first state and a second state, and isconfigured such that, when transitioning from the first state to thesecond state, a tissue-piercing element of the anchor moves with respectto the window of the respective suction chamber (e.g., past, or past atleast part of the window). For some applications, and as shown in FIGS.6A-C, implant 180 comprises a vacuum source 192, which is providedclosed, and is configured to be placed in fluid communication withsuction chambers 186, so as to draw at least a partial vacuum into thesuction chambers. Alternatively, implant 180 may be configured to beconnected to an external (e.g., extracorporeal) vacuum source such thatthe vacuum source is in fluid communication with the suction chambers.

FIG. 6A shows implant 180 having been delivered into tissue 182 of thesubject. Vacuum source 192 is not in fluid communication with suctionchambers 186. For example, a valve 196 may be disposed between thevacuum source and each suction chamber, and may be closed. Anchors 188are in the first state thereof. For example, each anchor may beconstrained in the first state (e.g., a constrained state) thereof by arespective constraining member 190.

Subsequently, vacuum source 192 is placed in fluid communication so asto draw at least a partial vacuum is drawn into suction chambers 186,such as by opening valves 196 (FIG. 6B). The at least partial vacuumdraws (e.g., sucks) a portion of tissue 182, via windows 194, intochambers 186, the tissue forming a bulge 183 of tissue within eachchamber, in the vicinity of each window.

Subsequently, anchors 188 transition into the second state thereof (FIG.6C). For example, constraining members 190 may release anchors 188, theanchors being configured to automatically transition toward the secondstate (e.g., an unconstrained state) when released. For example, anchors188 may comprise a spring and/or a shape memory material such asnitinol. As described hereinabove, each anchor is configured such that,when transitioning from the first state to the second state, atissue-piercing element of the anchor moves with respect to (e.g., past)the window of the respective suction chamber. When a bulge 183 isdisposed within each chamber in a vicinity of each window, thetissue-piercing element of each anchor thereby pierces the bulge oftissue, thereby anchoring implant 180 to the tissue.

It is hypothesized that anchors 188, which are disposed within suctionchambers 186, reduce a likelihood of inadvertently damaging tissue ofthe subject, compared with anchors that are disposed on the outside ofan implant. For some applications, the at least partial vacuum drawninto suction chambers 186 only lasts for a short duration (e.g., lessthan an hour, such as less than a minute, such as for a few seconds),and dissipates subsequent to the anchoring of anchors 188 to bulges 183.

Reference is made to FIGS. 7A-B, which are schematic illustrations of asystem 200 for use with a nerve 202 of a subject, in accordance withrespective applications of the invention. System 200 comprises one ormore helical electrodes 204 (e.g., a first helical electrode 204 a and asecond helical electrode 204 b), configured to be wrapped aroundrespective sites on nerve 202, an injectable implant 206, configured tobe percutaneously implanted in a vicinity of nerve 202, one or morewires 208 (e.g., a first wire 208 a and a second wire 208 b), couplingrespective helical electrodes to the injectable implant, and a helicalanchor 210, configured to be wrapped around another site on nerve 202,and comprising a brace 212, configured to be coupled to a portion ofeach wire 208 that is disposed between helical electrodes 204 and theinjectable implant. Anchor 210 and brace 212 are hypothesized to reducemechanical forces between implant 206 and electrodes 204. Furthermore,implant 206 is typically implanted close to electrodes 204, so as toreduce movement of the implant with respect to the electrodes caused bymovement of parts of the body (e.g., limbs) of the subject, therebyfurther reducing mechanical forces between the implant and theelectrodes.

System 200 comprises an antenna 214, configured to wirelessly receiveenergy, the implant being configured to receive the received energy fromthe antenna. In the application of the invention shown in FIG. 7A,implant 206 comprises antenna 214. In the application of the inventionshown in FIG. 7B, anchor 210 comprises antenna 214, which is wiredlycoupled via a third wire 208 c to implant 206.

Reference is made to FIGS. 8A-C, which are schematic illustrations of asystem 240 for use with a nerve 242 of a subject, in accordance withsome applications of the invention. System 240 comprises (1) a cuff body244, that comprises one or more electrodes 246 (e.g., a first electrode246 a and a second electrode 246 b) and at least one planar antenna 248,configured to wirelessly receive energy, and (2) circuitry 250,configured to use the received energy from the planar antenna to driveelectrodes 246 to apply a current to nerve 242.

Cuff body 244 has a first length L1 and a second length L2, lengths L1and L2 being mutually orthogonal. FIG. 8A shows system 240 with cuffbody 244 in an unrolled state in which the cuff body lies on a plane,and lengths L1 and L2 define an area of the cuff body on the plane. Asshown, planar antenna 248 is disposed parallel with the plane of thecuff body. Typically, antenna 248 is disposed within the material of thecuff body, and is hence represented by dotted lines. Electrodes 246 aretypically disposed on a first face 252 of the cuff body, the cuff bodyalso having a second face 254, and a thickness between the first faceand the second face. Typically, electrodes 246 a and 246, are disposedat opposite ends of length L2 from each other, and typically haverespective longest dimensions that are parallel to length L1.

Antenna 248 spans an area defined by a first length L3 and a secondlength L4 of the antenna, lengths L3 and L4 being mutually orthogonal.That is, antenna 248 defines spaces between a material from which it isformed (e.g., a wire), but as a whole, spans an area defined by lengthsL3 and L4. Typically, antenna 248 spans an area that is at least 70percent as great as the total area of the cuff body (defined by lengthsL1 and L2).

It is to be noted that throughout this application, including thespecification and the claims, the dimensions of planar antennas,including the terms “span” and “area”, refers to such an overalldimension (e.g., an overall span and overall area) of the antenna. Forsome applications, and as shown in FIG. 8A, antenna 248 is shaped togenerally define a rectangular spiral, having mutually orthogonallengths L3 and L4, which define an area that the antenna spans.

FIG. 8B shows system 240 with cuff body 244 wrapped around nerve 242,such that first face 252 and electrodes 246 face the nerve. It is to benoted that length L2 of cuff body 244 defines a length of nerve 242 thatis covered by the cuff body. FIG. 8C shows a cross-section through nerve242 and cuff body 244, showing antenna 248 disposed within the materialof cuff body 244.

Cuff body 244 defines a tube, first face 252 defining a 360-degreecircumferential wall of the tube. Antenna 248 (e.g., the area thereof)extends at least 180 degrees around the circumferential wall. That is,length L3 extends at least 180 degrees around the circumferential wall.Antenna 248 may extend at least 270 degrees, such as at least 330degrees, e.g., at least 360 degrees around the circumferential wall. Forexample, antenna 248 may circumscribe the circumferential wall.

Reference is made to FIGS. 9A-C, which are schematic illustrations of asystem 260 for use with nerve 242, in accordance with some applicationsof the invention. As described hereinabove, cuff body 244 of system 240comprises at least one planar antenna 248. FIGS. 8A-C show system 240comprising exactly one planar antenna 248. System 260 is identical tosystem 240, except that, instead of planar antenna 248, system 260comprises three planar antennas 268 (planar antenna 268 a, planarantenna 268 b, and planar antenna 268 c).

FIG. 9A shows system 260 with cuff body 244 in an unrolled state inwhich the cuff body lies on a plane, and lengths L1 and L2 define anarea of the cuff body on the plane. FIG. 9B shows a cross-sectional viewof system 260 with cuff body 244 wrapped around nerve 242, such thatfirst face 252 and electrodes 246 face the nerve. FIG. 9C is asimplified cross-sectional view, showing the position of the antennas ofcuff body 244 around nerve 242.

Each planar antenna of system 260 spans about 120 degrees around thecircumferential wall defined by first face 252 of cuff body 244. Forexample, respective lengths L3 a, L3 b, and L3 c of planar antennas 268a, 268 b, and 268 c, each span about one third of length L1 of cuff body244. Typically, a sum of the areas spanned by antennas 268 a, 268 b, and268 c is greater than the total area of the cuff body (defined bylengths L1 and L2). For example, the antennas may partly overlap eachother.

Reference is again made to FIGS. 8A-9C. It is to be noted that the gapsbetween the antennas shown in FIGS. 8A-9C are for clarity, and that thegaps between the antennas may in fact be very small, such as practicallynon-existent. For some applications, such as described hereinbelow withrespect to FIGS. 10-14, mutatis mutandis, antennas may overlap with eachother.

Reference is made to FIGS. 10-14, which are schematic illustrations ofplanar antenna configurations for systems such as system 240 and/orsystem 260, in accordance with respective applications of the invention.

FIG. 10 shows planar antennas 278 a and 278 b, which are typicallycomponents of a system 270 that is identical, except for the antennaconfiguration thereof, to system 240 and/or system 260, describedhereinabove. Planar antennas 278 a and 278 b each span 180 degreesaround the circumferential wall defined by first face 252 of cuff body244, and are typically rotationally offset with respect to each othersuch that (1) a first arc region 272 a of cuff body 244 comprisesoverlapping portions of both antennas, (2), a second arc region 272 b ofthe cuff body, disposed exactly opposite the first arc region, comprisesno portions of an antenna, and (3) two arc regions 272 c and 272 d,disposed rotationally between the first and second arc regions, eachcomprise portions of only one antenna. For some applications, and asshown with reference to FIG. 10, planar antennas 278 a and 278 b arerotationally offset by 90 degrees with respect to each other, such thateach arc region spans 90 degrees around the circumferential wall definedby first face 252. It is to be noted that any line that passes throughthe transverse cross-sectional center of system 270 passes throughexactly two antennas. Planar antennas 278 a and 278 b may bealternatively be offset by another number of degrees with respect toeach other, such as less than and/or greater than 90 degrees.

FIG. 11 shows planar antennas 288 a, 288 b, and 288 c, which aretypically components of a system 280 that is identical, except for theantenna configuration thereof, to system 240 and/or system 260,described hereinabove. Planar antennas 288 a, 288 b, and 288 c each span180 degrees around the circumferential wall defined by first face 252 ofcuff body 244, and are typically rotationally offset with respect toeach other such that (1) three first arc regions 282 a of cuff body 244each comprise overlapping portions of two antennas, and (2) three secondarc regions 282 b of the cuff body, each disposed exactly opposite arespective first arc region 282 a, each comprise a portion of oneantenna. For some applications, and as shown with reference to FIG. 11,planar antennas 288 a and 288 b are rotationally offset by 90 degreeswith respect to each other, and planar antennas 288 b and 288 c arerotationally offset by 45 degrees with respect to each other, such that(1) one of each type of arc region (i.e., one region 282 a and oneregion 282 b) spans 45 degrees around the circumferential wall definedby first face 252, and (2) two of each type of arc region span 45degrees around the circumferential wall. It is to be noted that any linethat passes through the transverse cross-sectional center of system 280passes through exactly three antennas. It is also to be noted that at noarc region of the cuff body do more than two antennas overlap. Planarantennas 288 a, 288 b, and 288 c may be alternatively be offset byanother number of degrees with respect to each other.

FIG. 12 shows planar antennas 298 a, 298 b and 298 c, which aretypically components of a system 290 that is identical, except for theantenna configuration thereof, to system 240 and/or system 260,described hereinabove. Planar antennas 298 a, 298 b, and 298 c each span180 degrees around the circumferential wall defined by first face 252 ofcuff body 244, and are typically rotationally offset with respect toeach other such that (1) three first arc regions 292 a, 292 b, and 292 cof cuff body 244 comprises overlapping portions of two antennas, and (2)three second arc regions 292 d, 292 e, and 292 f of the cuff body, eachdisposed exactly opposite a respective first arc region, each compriseportions of one antenna. For some applications, and as shown withreference to FIG. 12, planar antennas 298 a, 298 b, and 298 c arerotationally offset by 120 degrees with respect to each other, such thateach arc region spans 60 degrees around the circumferential wall definedby first face 252. It is to be noted that any line that passes throughthe transverse cross-sectional center of system 290 passes throughexactly three antennas. It is also to be noted that at no arc region ofthe cuff body do more than two antennas overlap. Planar antennas 278 aand 278 b may alternatively be offset by another number of 180 degreeswith respect to each other.

FIGS. 13 and 14 show systems 300 and 310, respectively, each comprisingthree planar antennas (308 a, 308 b and 308 c; and 318 a, 318 b and 318c, respectively) that are rotationally offset with respect to each otherby 60 degrees. Planar antennas 308 a, 308 b and 308 c of system 300 eachspan 180 degrees around circumferential wall defined by first face 252of cuff body 244, and planar antennas 318 a, 318 b and 318 c of system310 each span 120 degrees around the circumferential wall. It is to benoted that any line that passes through the transverse cross-sectionalcenter of system 300 passes through exactly three antennas, and any linethat passes through the transverse cross-sectional center of system 310passes through exactly two antennas.

It is to be further noted that systems 270, 300 and 310 each define anarc region that does not comprise any portions of an antenna (arc region272 b of system 270, an arc region 302 a of system 300, and an arcregion 312 a of system 310). It is hypothesized that such regionsadvantageously facilitate cuff body 244 being openable and/or beingprovided in an open state (e.g., for subsequent wrapping around nerve242). For example, although not shown in the figures, cuff body 244 mayhave a discontinuity at such a region.

Reference is made to FIG. 15, which is a schematic illustration of ahelical element 320 comprising a helical body 322 and a plurality ofplanar antennas 328, in accordance with some applications of theinvention. Typically, helical body 322 comprises a helical cuff body,configured to be wrapped around a nerve of a subject. Helical element320 has a central longitudinal axis 321, around which helical body 322forms a circumferential wall that typically spans at least once aroundaxis 321. It is to be noted that helical body 322 thereby forms a360-degree circumferential wall around axis 321, albeit disposed alongaxis 321 according to the pitch of the helix. Planar antennas 328 aretypically disposed within the material of helical body 322. Each planarantenna 328 spans less than 360 degrees around the circumferential wallformed by body 322 (e.g., spans less than one complete turn of thehelix). Each planar antenna 328 is typically disposed such that alongest length of the antenna is generally parallel with the helix ofhelical body 322 (e.g., is shaped to define an incomplete turn of ahelix). Planar antennas 328 are disposed progressively along the helix,such that together the antennas form a broken helix within, and parallelto, the helix of helical body 322. Typically, each planar antenna 328spans no more than 180 degrees around the circumferential wall formed bybody 322.

For some applications, and as shown in FIG. 15, helical element 320comprises three planar antennas 328 a, 328 b, and 328 c, each of theplanar antennas spanning 180 degrees around the circumferential wallformed by body 322 (e.g., spans half a complete turn of the helix).Planar antenna 238 b is rotationally offset by 225 degrees with respectto planar antenna 328 a (e.g., antenna 238 b is offset by ⅝ of a turn ofthe helix with respect to antenna 328 a). That is, there is a 45 degreegap around the circumferential wall defined by body 322, between planarantennas 328 a and 328 b (e.g., there is a ⅛ turn of the helix betweenantennas 328 a and 328 b). Planar antenna 328 c is rotationally offsetwith respect to planar antenna 328 b to the same degree as planarantenna 328 b is rotationally offset with respect to planar antenna 328a. It is to be noted that, viewed from an end of helical element 320,planar antennas 328 a, 328 b, and 328 c have a similar arrangement toplanar antennas 288 a, 288 b, and 288 c of system 280 (e.g., thearrangement of antennas 288 a, 288 b, and 288 c may be “projected” ontoa helical element). Similarly, any of the antenna arrangements describedwith reference to FIGS. 8A-14 may be projected onto a helical element.

Reference is again made to FIGS. 11, 12, and 15. It is to be noted that,for some applications, such as those described with reference to FIGS.11, 12, and 15, each of a plurality of planar antennas spans less than360 degrees (e.g., no more than 180 degrees) around the longitudinalaxis of the cuff and/or helical body, but that all together, theplurality of planar antennas typically spans at least 360 degrees aroundthe longitudinal axis (i.e., at least one of the planar antennas isdisposed in each rotational position around the longitudinal axis).

Reference is again made to FIGS. 10-14. It is to be noted that, for someapplications in which a cuff body comprises a plurality of overlappingplanar antennas, a sum of the areas spanned by the plurality of planarantennas is greater than the area of the cuff body (e.g., the area of aface thereof).

Reference is made to FIGS. 16-18, which are schematic illustrations ofsystems comprising an implant 400, and at least one longitudinal memberhaving a distal portion configured to be implanted with the implant, anda proximal portion configured to remain outside of the subject, inaccordance with some applications of the invention. For someapplications, implant 400 comprises another implant described herein(e.g., implant 22, implant 52, implant 70, implant 92, implant 170,implant 180 or implant 206).

FIG. 16 shows a longitudinal member 420, reversibly couplable to implant400 via a locking mechanism 428, which is actuatable from outside of thesubject. When implant 400 is percutaneously delivered (e.g., injected)into tissue 10 of the subject, a distal portion 422 of longitudinalmember 420 that is coupled to the implant remains coupled to theimplant, such that portion 422 is also disposed within the tissue of thesubject (e.g., becomes implanted). A proximal portion 424 oflongitudinal member 420 remains outside the body of the subject, and istypically secured to a skin surface 404 of the subject (e.g., using tape426). Typically, longitudinal member 420 is configured to remain in thisstate for a period of at least 1 day. During this period, longitudinalmember 420 may be used to move the implant, e.g., to adjust a positionand/or orientation of the implant within tissue 10, and/or to withdrawthe implant from the tissue. Longitudinal member 420 is configured to bedecoupled from implant 400 by actuating locking mechanism 428, e.g., ifit is desirable that implant 400 remain in its position (e.g.,permanently). Longitudinal member 420 may be flexible or rigid, and maybe shaped as a wire, a rod, a strip, a tube, or any other suitableshape.

FIG. 17 shows a longitudinal member 430, reversibly coupled to implant400. Longitudinal member 430 is coupled to implant 400 by being loopedthrough an eyelet 438 defined by implant 400, such that two generallyparallel domains 431 a, 431 b of the longitudinal member are defined.When implant 400 is percutaneously delivered (e.g., injected) intotissue 10 of the subject, a distal portion 432 of longitudinal member430 that is coupled to the implant remains coupled to the implant, suchthat portion 432 is also disposed within the tissue of the subject(e.g., becomes implanted). A proximal portion 434 of longitudinal member430 remains outside the body of the subject, and is typically secured toskin surface 404 of the subject (e.g., using tape 426). Typically,longitudinal member 430 is configured to remain in this state for aperiod of at least 1 day. Subsequent to implantation of implant 400,longitudinal member 430 may be used to move the implant, e.g., to adjusta position and/or orientation of the implant within tissue 10, and/or towithdraw the implant from the tissue. Longitudinal member 430 isconfigured to be decoupled from implant 400 by being unthreaded fromeyelet 438, e.g., by one of the domains (e.g., domain 431 a) beingpulled, thereby pulling the other one of the domains (e.g., domain 431b) through and out of the eyelet. Longitudinal member 430 is typicallyflexible, and may be shaped as a wire, a strip, or any other suitableshape. For some applications, longitudinal member 430 comprises suture.

For some applications, implant 400 is delivered (e.g., injected) througha tubular longitudinal member 440, and the tubular longitudinal memberremains partially implanted subsequent to delivery of the implant (FIG.18). For some applications, tubular longitudinal member 440 comprisesimplant-storage member 24, described hereinabove. For some applications,tubular longitudinal member 440 comprises implant-storage member 60,described hereinabove. For some applications, tubular longitudinalmember 440 comprises implant-storage member 100 and/or distal portion 98of delivery tool 94, described hereinabove. For some applications,tubular longitudinal member 440 comprises delivery tube 152, describedhereinabove. Following delivery of implant 400 to tissue 10, a distalportion 442 of tubular longitudinal member 440 remains disposed withinthe tissue, such as slightly proximal to the implant (e.g., distalportion 442 becomes implanted). A proximal portion 444 of tubularlongitudinal member 440 remains outside the body of the subject, and istypically secured to a skin surface of the subject (e.g., using tape426). Typically, tubular longitudinal member 440 is configured to remainin this state for a period of at least 1 day. Subsequent to implantationof implant 400, tubular longitudinal member 440 may be used to accessthe implant, e.g., to facilitate adjusting a position and/or orientationof the implant within tissue 10, and/or to withdraw the implant from thetissue (e.g., via the tubular longitudinal member). Although FIG. 18shows tubular longitudinal member 440 being used in combination withlongitudinal member 430, it is to be noted that tubular longitudinalmember 440 may alternatively be used alone, or in combination withlongitudinal member 420.

Reference is again made to FIGS. 16-18. Typically, longitudinal member420, longitudinal member 430, and tubular longitudinal member 440 are atleast in part flexible, so as to facilitate placement of the proximalportion thereof against skin surface 404 (and securing thereto).

It will be appreciated by persons skilled in the art that the presentinvention is not limited to what has been particularly shown anddescribed hereinabove. Rather, the scope of the present inventionincludes both combinations and subcombinations of the various featuresdescribed hereinabove, as well as variations and modifications thereofthat are not in the prior art, which would occur to persons skilled inthe art upon reading the foregoing description.

The invention claimed is:
 1. Apparatus, comprising: an implant,comprising an implant body and at least one electrode disposed on theimplant body; and a hollow needle, shaped to define a space that isdimensioned to house the implant, and configured to be percutaneouslyadvanceable into tissue of a subject while the implant is disposedwithin the space, wherein: the apparatus is configured, while (a) the atleast one electrode is disposed within the space, and (b) the hollowneedle is disposed within the tissue, (i) to place the at least oneelectrode in electrical contact with the tissue, and (ii) to apply anapplication of current via the at least one electrode to the tissue, theimplant is deployable from the space, via an opening defined by thehollow needle, subsequently to the application of current by the implantto the tissue, and the hollow needle is percutaneously withdrawable fromthe tissue (i) subsequently to deployment of the implant from the space,and (ii) such that the implant remains in the tissue.
 2. The apparatusaccording to claim 1, wherein the hollow needle is shaped to define atleast one window, configured such that, while the implant is disposedwithin the space and the hollow needle is disposed in the tissue, theelectrical contact is via the window, and the window facilitates flow ofthe current therethrough between the at least one electrode and thetissue.
 3. The apparatus according to claim 2, further comprising adelivery manipulator, reversibly couplable to the implant, andconfigured to facilitate deployment of the implant through the openingby remaining stationary with respect to the tissue while the hollowneedle is withdrawn proximally with respect to the tissue.
 4. Theapparatus according to claim 3, wherein the hollow needle: has aproximal end, has a distal end that defines the opening, and has alateral wall that defines the window between the proximal end and thedistal end.
 5. The apparatus according to claim 1, further comprising alongitudinal member: having a distal end configured to be percutaneouslyadvanced into the subject while coupled to the implant, having aproximal end configured to be secured to a skin surface of the subject(1) while the distal end of the longitudinal member remains coupled tothe implant within the subject, and (2) for a duration of at least 1day, and being configured to move the implant within the subject bybeing moved.
 6. The apparatus according to claim 1, wherein: the implantcomprises at least two electrodes, the hollow needle is shaped to defineat least two windows, and the implant is configured to be disposedwithin the space such that each of the electrodes is aligned with arespective window of the at least two windows.
 7. The apparatusaccording to claim 1, wherein: the implant body has a proximal end and adistal end, and a longitudinal axis between the proximal end and thedistal end; the implant comprises at least one distal anchor, coupled tothe implant body, and configured to inhibit movement of the implant bodythrough the tissue in a distal direction more than in a proximaldirection; and at least one proximal anchor, coupled to the implantbody, disposed proximally from the distal anchor, and configured toinhibit movement of the implant body through the tissue in the proximaldirection more than in the distal direction.
 8. The apparatus accordingto claim 7, wherein: the distal anchor comprises at least one barb thatprotrudes, in the distal direction, at a nonzero angle with respect tothe longitudinal axis of the implant body, and the proximal anchorcomprises at least one barb that protrudes, in the proximal direction,at a nonzero angle with respect to the longitudinal axis of the implantbody.
 9. The apparatus according to claim 8, wherein: each of theanchors has a constrained state and an unconstrained state, each of theanchors is configured such that the nonzero angle of the barb of eachanchor is smaller in the constrained state of the anchor than in theunconstrained state of the anchor.
 10. The apparatus according to claim9, wherein: the implant is bidirectionally movable through the opening,the hollow needle is configured (i) to constrain each of the anchors inthe respective constrained state thereof while the respective anchor isdisposed within the space, and (ii) to move the distal anchor into theconstrained state thereof when the distal anchor is moved through theopening into the space; and the apparatus further comprises a deliverymanipulator, reversibly couplable to the implant, and configured tofacilitate bidirectional movement of the implant through the opening.11. A method, comprising: percutaneously placing an implant withintissue of a subject while the implant is disposed within a lumen of ahollow needle, the implant including at least one electrode; while theelectrode remains disposed within the lumen, activating the implant toapply current to the tissue; and subsequently to the application ofcurrent by the implant, deploying the implant from the hollow needle;and subsequently, withdrawing the hollow needle from the subject whilethe implant remains within the tissue.
 12. The method according to claim11, wherein: the application of current is a first application ofcurrent, the method further comprises: measuring a physiologicalresponse of the subject to the first application; in response to themeasured physiological response to the first application, repositioningthe implant in the tissue while the implant remains disposed within thelumen; and measuring a physiological response of the subject to a secondapplication of current applied, while the implant is disposed within thelumen, by the implant to the tissue, and deploying the implant from thehollow needle comprises deploying the from the hollow needle in responseto the measured physiological response to the second application. 13.The method according to claim 11, wherein the hollow needle is shaped todefine a window in a lateral wall of the hollow needle, the lateral wallcircumscribing the lumen, and wherein placing the implant comprisesplacing the implant such that the implant is aligned, within the lumen,with the window, such that the application of current is applied by theimplant to the tissue via the window.
 14. The method according to claim13, wherein the window is a first window, the implant includes a firstelectrode and a second electrode on an outer surface of the implant, thehollow needle is shaped to define a second window in the lateral wall,and wherein placing the implant comprises placing the such that thefirst and second electrodes are aligned, within the lumen, with thefirst and second windows, respectively, such that the application ofcurrent is applied by the first and second electrodes to the tissue viathe first and second windows.
 15. The method according to claim 11,wherein the implant includes (i) an implant body having a distal end anda proximal end, (ii) an expandable distal anchor, (iii) at least twoelectrodes disposed on the implant body, and (iv) an expandable proximalanchor disposed proximally to the distal anchor and to the electrodes,and wherein the method further comprises: subsequently to the step ofplacing, putting the implant into a partially-exposed state (a) in which(i) the distal anchor is exposed from the lumen, and is expanded; (ii)the at least two electrodes are exposed from the lumen, and (iii) theproximal anchor remains disposed within the lumen, and (b) such that theapplication of current is applied while the implant is in thepartially-exposed state.
 16. The method according to claim 15, whereinputting the implant into the partially-exposed state comprises puttingthe implant into the partially-exposed state in which the distal anchor(i) is expanded, and (ii) inhibits movement of the body through thetissue in a distal direction more than in a proximal direction.
 17. Themethod according to claim 15, wherein: the application of current is afirst application of current, the method further comprises: measuring aphysiological response of the subject to the first application; inresponse to the measured physiological response to the firstapplication, repositioning the implant in the tissue; and measuring aphysiological response of the subject to a second application of currentapplied by the repositioned implant, and deploying the implant from thehollow needle comprises deploying the from the hollow needle (i) inresponse to the measured physiological response to the secondapplication, and (ii) such that the proximal anchor expands.
 18. Themethod according to claim 17, wherein deploying the implant comprisesexposing the proximal anchor from the lumen such that the proximalanchor (i) expands, and (ii) inhibits movement of the implant bodythrough the tissue in a proximal direction more than in a distaldirection.
 19. The method according to claim 17, wherein repositioningthe implant comprises (i) returning the electrodes and the distal anchorinto the lumen (ii) subsequently repositioning the implant and thehollow needle, and (iii) subsequently returning the implant to thepartially-exposed state.
 20. The method according to claim 17, whereinrepositioning the implant comprises moving the hollow needle and theimplant proximally while the implant remains in the partially-exposedstate.